I have yet to see an actual photo or detailed diagram of the backside of PN HR3Z-63043B13-BD on any dealer or part supply website. Haven't seen one on a google web search either. May have to actually visit a dealer that has one and have them show it to you.
Here's a few:
https://parts.lakelandford.com/p/Ford__Mustang/Steering-Wheel-Air-Bag/70204835/HR3Z63043B13BD.html?partner=googlebase
https://parts.nplincoln.com/p/Ford__Mustang/Steering-Wheel-Air-Bag/70204835/HR3Z63043B13BD.html?partner=googlebase